In spite of the fact that the study of development of carcinostatics are being carried out energetically on a worldwide scale, none of currently used effective carcinostatics are employed without anxiety because of the side effects. Also, in view of the current state that, among physicotherapies, there is no effective and noticeable one that gives less load, it is desired to develop satisfactory carcinostatics as soon as possible.
Taking this into consideration, the present applicant suggested inhibiting agents against the proliferation of malignant tumor cells of human beings in U.S. Pat. Nos. 4,810,495 and 4,963,358 and a process for the preparation of an inhibiting agent against the proliferation of malignant tumor cells of animals in U.S. Pat. No. 4,595,657.
However, in those patents, the substances that inhibit the proliferation of malignant tumor cells were unclear.
Further, the present applicant suggested an inhibiting agent against the proliferation of malignant tumor cells of human beings comprising 2-hydroxy-1-(P-hydroxyphenyl)-5-methylhexane-3-one in Japanese Patent Tokkai-hei 2-247121 (Laid-Open No. 247121/1995), an inhibiting agent against the proliferation of malignant tumor cells of human beings comprising a monoglyceride in Japanese Patent Tokkai-hei 2-247125 (Laid-Open No. 247125/1995), and an inhibiting agent against the proliferation of malignant tumor cells of human beings comprising 2-heptadecanol in Japanese Patent Tokkai-hei 2-247120 (Laid-Open No. 247120/1995).
The object of the present invention is. to provide an inhibiting agent against the proliferation of tumor cells which is not any of the substances that were suggested in the above inventions, does not affect at all, in a toxicity test using normal cells, their proliferation, further in a test of the inhibition of proliferation of tumor cells of human beings transplanted in nude mice, stops the proliferation several days after the start of the administration as well as permits the tumor to reduce significantly in spite of the absence of followed administration, shows stable effectiveness by hypodermic administration, and has a stable prolonged action in organisms.